FKIE_CVE-2026-4438

Vulnerability from fkie_nvd - Published: 2026-03-20 20:16 - Updated: 2026-04-07 18:40
Severity ?
5.4 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Summary
Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C library version 2.34 to version 2.43 could result in an invalid DNS hostname being returned to the caller in violation of the DNS specification.
References
3ff69d7a-14f2-4f67-a097-88dee7810d18https://sourceware.org/bugzilla/show_bug.cgi?id=34015Exploit, Issue Tracking, Patch
Impacted products
Vendor Product Version
gnu glibc *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "1ECF98C3-1D14-492E-9FE0-241B03BF8550",
              "versionEndIncluding": "2.43",
              "versionStartIncluding": "2.34",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library\u0027s DNS backend in the GNU C library version 2.34 to version 2.43 could result in an invalid DNS hostname being returned to the caller in violation of the DNS specification."
    },
    {
      "lang": "es",
      "value": "Llamar a gethostbyaddr o gethostbyaddr_r con un nsswitch.conf configurado que especifica el backend DNS de la biblioteca en la biblioteca GNU C versi\u00f3n 2.34 a la versi\u00f3n 2.43 podr\u00eda resultar en que se devuelva un nombre de host DNS no v\u00e1lido al llamador en violaci\u00f3n de la especificaci\u00f3n DNS."
    }
  ],
  "id": "CVE-2026-4438",
  "lastModified": "2026-04-07T18:40:02.177",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.4,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 2.5,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-20T20:16:49.623",
  "references": [
    {
      "source": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch"
      ],
      "url": "https://sourceware.org/bugzilla/show_bug.cgi?id=34015"
    }
  ],
  "sourceIdentifier": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        }
      ],
      "source": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-88"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}


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